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Design and fabrication of compact Ge-on-SOI coupling structure
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作者 Jianfeng GAO Junqiang SUN +2 位作者 Heng ZHOU Jialin JIANG Yang ZHOU 《中国光电子学前沿:英文版》 EI CSCD 2019年第3期276-285,共10页
In this paper, we have proposed and demonstrated a simple approach to fabricate vertical integrated structure for coupling between active germanium (Ge) waveguide and silicon-on-insulator (SOI) waveguide. The active G... In this paper, we have proposed and demonstrated a simple approach to fabricate vertical integrated structure for coupling between active germanium (Ge) waveguide and silicon-on-insulator (SOI) waveguide. The active Ge waveguide is sputtered after etching the underlying passive silicon (Si) waveguide. This method scuttles away from the difficulty involved in the waveguide fabrication by avoiding the etching process for the Ge waveguide, and thereby the waveguide quality is improved. The influences of the coupling structural parameters on the coupling loss are analyzed and discussed. The optimizing parameters are obtained for the fabrication. The minimal coupling loss is experimentally measured about 2.37 dB, and variation tendency of coupling loss against the structural parameters is consistent with the theoretical result. The proposed approach offers an effective path for vertical coupling between Ge and SOI optical components. 展开更多
关键词 taper COUPLER integrated optics DEVICE guided waves SILICON-ON-INSULATOR (SOI) WAVEGUIDE germanium (Ge) WAVEGUIDE active Ge DEVICE Ge-on-SOI coupling structure
Effect of Walking Speed Intervention for Stroke Hemiplegia Using Neurorehabilitation-Robot 预览
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作者 Hirofumi Tanabe Toshimasa Mikawa +1 位作者 Akihiko Kondo Hiroshi Tanabe 《健康(英文)》 2019年第11期1487-1492,共6页
Sufficient hip joint extension range of motion is important in improving the walking speed of patients with spastic hemiplegia. In this study, we developed a piston device for the hip (PDH) that simulates the action o... Sufficient hip joint extension range of motion is important in improving the walking speed of patients with spastic hemiplegia. In this study, we developed a piston device for the hip (PDH) that simulates the action of the piston technique for hip joints (PTH), which is a method for improving hip joint extension range of motion. We then evaluated the efficacy of PDH on 10 spastic hemiplegia patients suffering from a limited range of hip joint extension. Results confirmed rapid improvement of hip joint range of motion and increase in walking speed. 展开更多
关键词 Device GAIT Step LENGTH HEMIPLEGIA
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Fuzzy mathematics and game theory based D2D multicast network construction 预览
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作者 LI Zhuoming CHEN Xing +3 位作者 ZHANG Yu WANG Peng QIANG Wei LIU Ningqing 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第1期13-21,共9页
Device to device (D2D) multi-hop communication in multicast networks solves the contradiction between high speed requirements and limited bandwidth in regional data sharing communication services. However, most networ... Device to device (D2D) multi-hop communication in multicast networks solves the contradiction between high speed requirements and limited bandwidth in regional data sharing communication services. However, most networking models demand a large control overhead in eNodeB. Moreover, the topology should be calculated again due to the mobility of terminals, which causes the long delay. In this work, we model multicast network construction in D2D communication through a fuzzy mathematics and game theory based algorithm. In resource allocation, we assume that user equipment (UE) can detect the available frequency and the fuzzy mathematics is introduced to describe an uncertain relationship between the resource and UE distributedly, which diminishes the time delay. For forming structure, a distributed myopic best response dynamics formation algorithm derived from a novel concept from the coalitional game theory is proposed, in which every UE can self-organize into stable structure without the control from eNodeB to improve its utilities in terms of rate and bit error rate (BER) while accounting for a link maintenance cost, and adapt this topology to environmental changes such as mobility while converging to a Nash equilibrium fast. Simulation results show that the proposed architecture converges to a tree network quickly and presents significant gains in terms of average rate utility reaching up to 50% compared to the star topology where all of the UE is directly connected to eNodeB. 展开更多
关键词 DEVICE to DEVICE (D2D) communication MULTICAST network fuzzy LOGIC GAME theory TREE architecture
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塑料袋收纳装置设计研究 预览 被引量:1
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作者 亢净 《设计》 2019年第4期119-121,共3页
为解决塑料袋收纳的问题,对塑料袋收纳装置进行优化设计。通过对相关的现有塑料袋收纳产品进行市场调查、消费者调查、专利查询,确定立项的意义。然后采用产品设计方法提出设计方案,对不同方案、不同结构进行对比和评价,完善产品结构,... 为解决塑料袋收纳的问题,对塑料袋收纳装置进行优化设计。通过对相关的现有塑料袋收纳产品进行市场调查、消费者调查、专利查询,确定立项的意义。然后采用产品设计方法提出设计方案,对不同方案、不同结构进行对比和评价,完善产品结构,优化产品外观,合理控制产品成本及质量。可突破已有塑料袋收纳类产品的传统印象,提升产品的实用性,体现设计改变生活的力量。 展开更多
关键词 塑料袋 收纳 卫生 装置
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Analysis of global momentum transfer due to buried mine detonation 预览
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作者 N.Heider V.Denefeld H.Aurich 《Defence Technology(防务技术)》 CAS CSCD 2019年第5期821-827,共7页
The emergence of improvised explosive devices (IED) significantly extended the spectrum of possiblethreat mechanisms to military vehicles and their occupants. Especially buried high explosive (HE)charges lead to new a... The emergence of improvised explosive devices (IED) significantly extended the spectrum of possiblethreat mechanisms to military vehicles and their occupants. Especially buried high explosive (HE)charges lead to new and originally not investigated loading conditions during their detonation. It is theinteraction of the embedding geomaterial with the detonation products that leads to a strongly increasedglobal impulse transfer on the vehicle with following high accelerations on the vehicle occupant. Thispaper presents a comprehensive approach for the analysis of occupant loading. In a first step, we presentthe so called ring technology which allows the experimental determination of the locally resolvedspecific impulse distribution on a vehicle floor due to buried charge detonation. A complementarymethod is the use of scaled model vehicles that allows the determination of global vehicle loading parameterssuch as jump height or vehicle accelerations. Both techniques were used to study the influenceof burial conditions as burial depth, embedding material or water content on the impulse transfer ontothe vehicle. These experimental data are used to validate material models for the embedding sand orgravel materials. This validated material description is the basis for numerical simulation models used inthe assessment of occupant safety. In the last step, we present a simulation model for a generic militaryvehicle including a Hybrid III occupant dummy that is used for the determination of biomechanicaloccupant exposure levels. Typical occupant loadings are evaluated and correlated with burial conditionsas HE mass and global momentum transfer. 展开更多
关键词 Improvised EXPLOSIVE device VEHICLE protection OCCUPANT loading
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一种罗茨泵转子间隙调整装置 预览
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作者 陈曙华 《科技创新与应用》 2019年第32期63-64,共2页
相比其他泵的压缩比来说,罗茨泵处于较低的水平,所以罗茨泵这种设备属于无内压缩的真空并,同时,在一般情况下,需要在高真空泵或中真空泵前设置前级泵。在很多行业中,罗茨泵都有广泛的应用,所以罗茨泵的相关调试技术也成为各个行业技术... 相比其他泵的压缩比来说,罗茨泵处于较低的水平,所以罗茨泵这种设备属于无内压缩的真空并,同时,在一般情况下,需要在高真空泵或中真空泵前设置前级泵。在很多行业中,罗茨泵都有广泛的应用,所以罗茨泵的相关调试技术也成为各个行业技术人员主要关注的问题。文章针对一种罗茨泵转子间隙调整装置进行了介绍,旨在明确罗茨泵转子间隙调整的相关技术原理,并明确具体的调整方法。 展开更多
关键词 罗茨泵 转子间隙调整 装置 原理
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Nanogenerator-Based Self-Charging Energy Storage Devices 预览
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作者 Kun Zhao Yuanhao Wang +4 位作者 Lu Han Yongfei Wang Xudong Luo Zhiqiang Zhang Ya Yang 《纳微快报:英文版》 CAS CSCD 2019年第2期5-23,共19页
One significant challenge for electronic devices is that the energy storage devices are unable to provide su cient energy for continuous and long-time operation,leading to frequent recharging or inconvenient battery r... One significant challenge for electronic devices is that the energy storage devices are unable to provide su cient energy for continuous and long-time operation,leading to frequent recharging or inconvenient battery replacement.To satisfy the needs of next-generation electronic devices for sustainable working,conspicuous progress has been achieved regarding the development for nanogenerator-based self-charging energy storage devices.Herein,the development of the self-charging energy storage devices is summarized.Focus will be on preparation of nanomaterials for Li-ion batteries and supercapacitors,structural design of the nanogenerator-based self-charging energy storage devices,performance testing,and potential applications.Moreover,the challenges and perspectives regarding self-charging energy storage devices are also discussed. 展开更多
关键词 NANOMATERIAL NANOGENERATOR Energy STORAGE DEVICE Self-charging
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智能总保故障排查成本控制的解决方案 预览
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作者 吴城 吴宇红 纪涛 《湖州师范学院学报》 2019年第2期62-67,共6页
智能总保投入运行后,由于剩余电流超限和频繁动作预警故障,排查时造成了基层供电所工作量剧增、排查时间过长、故障点定位难等问题.基于此,研究一款不需要拆卸线路使用,且可以根据故障点的排查要求进行现场实测或临时安装远程监测的漏... 智能总保投入运行后,由于剩余电流超限和频繁动作预警故障,排查时造成了基层供电所工作量剧增、排查时间过长、故障点定位难等问题.基于此,研究一款不需要拆卸线路使用,且可以根据故障点的排查要求进行现场实测或临时安装远程监测的漏电跟踪分析记录装置.经实践检验,该装置取得了临时安装零停电、客户用电零影响、故障排查零返工的成效,还使优质服务得到提升,检修作业安全风险得到降低,智能总保运维检修成本得到有效控制. 展开更多
关键词 智能总保 剩余电流 装置 远程监测
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A Smartphone-assisted Paper-based Analytical Device for Fluorescence Assay of Hg2+
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作者 YE Jiavven GENG Yijia +5 位作者 CAO Fanghao SUN Dan XU Shuping CHANG Jingjing XU Weiqing CHEN Qidan 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第6期972-977,共6页
Rapid,efficiency and portable detection systems in low-resource settings with limited laboratory equipment and technical expertise are urgently needed.Herein,an integrated platform composed of a paper-based analytical... Rapid,efficiency and portable detection systems in low-resource settings with limited laboratory equipment and technical expertise are urgently needed.Herein,an integrated platform composed of a paper-based analytical device and a smartphone detection system for Hg^2+ onsite testing was developed.Nitrogen-doped carbon dots(N-CDs)were synthesized by a simple hydrothermal method using citric acid as the carbon source and ethanediamine as the nitrogen source,which gave out bright blue fluorescence under the excitation at 350 nm UV light and the absolute fluorescence quantum yield was 17.1%.The fluorescence of the prepared N-CDs can be effectively quenched by Hg^2+.In addition,an external attachment of smartphone for illumination and external light interference was designed to trace the fluorescence signals,and a software application of Android system with simple operation program was developed to perform snapshot and image processing.The smartphone-assisted detection system was combined with the N-CDs decorated paper chip to achieve the sensitive detection of Hg^2+ in water samples.This integrated method for reliable sensing of Hg^2+ shows a good linear detection range of 10–800µmol/L(R2=0.9595)with detection limit of 1.07×10^−8 mol/L. 展开更多
关键词 Paper-based analytical device Nitrogen-doped carbon dot Integrated sensing platform Mercury ion
一种用绝压传感器实现的全压压力测量装置 预览
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作者 孙和泰 郭知明 叶加星 《液压气动与密封》 2019年第2期67-68,71共3页
该文介绍了一种用绝压传感器实现的全压压力测量装置的设计方案,主要是用一只绝压传感器实现绝压、正压、负压的测量,极大降低了压力检定装置的制造成本。
关键词 绝压传感器 正压 负压 装置
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激光对焊装置的设计与研究 预览
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作者 朱娇仪 杨应洪 +2 位作者 尹显明 周辽 张国彬 《机械工程与自动化》 2019年第4期119-120,共2页
针对航空、常规生产加工等工件的焊接环节,设计了一套新型激光对焊装置。介绍了该装置的基本结构和工作方法,并进行了三维建模及制作。该装置具有操作简单、维护方便等优点,可应用于批量生产中,提高了生产效率。该项目的实施对后续产品... 针对航空、常规生产加工等工件的焊接环节,设计了一套新型激光对焊装置。介绍了该装置的基本结构和工作方法,并进行了三维建模及制作。该装置具有操作简单、维护方便等优点,可应用于批量生产中,提高了生产效率。该项目的实施对后续产品的研究、改进及自动化生产具有较高的参考价值。 展开更多
关键词 激光 焊接 装置 设计
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A wireless-communication-based measurement of gas pressure with capsule-slime sealing device 预览
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作者 Zhengyan Wu Deqiang Fan +4 位作者 Shuguang Jiang Hao Shao Kai Wang Weiqing Zhang Chaowei Guo 《矿业科学技术学报:英文版》 CSCD 2019年第6期917-923,共7页
To solve the existing problems of imperfect sealing and the inaccurate measurement of gas pressure in traditional sealing,the present study builds a new model of capsule-slime sealing device based on wireless pressure... To solve the existing problems of imperfect sealing and the inaccurate measurement of gas pressure in traditional sealing,the present study builds a new model of capsule-slime sealing device based on wireless pressure gauge.The new sealing device is mainly composed of two sets of capsules,a capsule connecting piece and a slime part,measures the pressure through the wireless communication technology,and seals through chemical reaction in the capsule,which generates gas to expand the capsule and extrude the pre-stored slime.Two methods of extruding pre-stored slime are proposed:in the first method,transverse force is generated by the expansion of the capsules at both ends,pushing the capsules toward the middle through the chute and squeezing the pre-stored slime out;in the second,high-pressure gas generated in the capsules is led into the expansion tube,which is inserted into the storage tube,squeezing it and letting the slime out to complete the sealing process.Then the research studies the effect of sealing under the condition of drilling with the structure of slime storage tube.The results indicate that the maximum standing time of slime wrapped in metal net is 2 h,instead of the expected 10 d,failing to meet the sealing requirements.When the slime viscosity is 1200–3000 m Paás in the structure of slime storage tube,the best viscosity of slime is achieved and can simulate sealing the drilling hole(5–4,4–2.36,2.36–1.18,1.18–0.15 mm in diameter),as well as the gap caused by mixed sand accumulation. 展开更多
关键词 Wireless pressure gauge Capsule-slime Hole sealing device Simulated sealing
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半潜式风、潮流联合发电平台水动力分析 预览
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作者 马勇 胡超 +2 位作者 周丙浩 李磊 康有为 《船舶与海洋工程学报:英文版》 CSCD 2019年第1期72-81,共10页
Energy shortages and environmental pollution are becoming increasingly severe globally. The exploitation and utilization of renewable energy have become an effective way to alleviate these problems. To improve power p... Energy shortages and environmental pollution are becoming increasingly severe globally. The exploitation and utilization of renewable energy have become an effective way to alleviate these problems. To improve power production capacity, power output quality, and cost effectiveness, comprehensive marine energy utilization has become an inevitable trend in marine energy development. Based on a semi-submersible wind-tidal combined power generation device,a three-dimensional frequency domain potential flow theory is used to study the hydrodynamic performance of such a device. For this study, the RAOs and hydrodynamic coefficients of the floating carrier platform to the regular wave were obtained. The influence of the tidal turbine on the platform in terms of frequency domain was considered as added mass and damping. The direct load of the tidal turbine was obtained by CFX.FORTRAN software was used for the second development of adaptive query workload aware software, which can include the external force. The motion response of the platform to the irregular wave and the tension of the mooring line were calculated under the limiting condition(one mooring line breakage). The results showed that the motion response of the carrier to the surge and sway direction is more intense, but the swing amplitude is within the acceptable range. Even in the worst case scenario, the balance position of the platform was still in the positioning range, which met the requirements of the working sea area. The safety factor of the mooring line tension also complied with the requirements of the design specification. Therefore, it was found that the hydrodynamic performance and motion responses of a semi-submersible wind-tidal combined power generation device can meet the power generation requirements under all design conditions, and the device presents a reliable power generation system. 展开更多
关键词 Power generation device Coupling HYDRODYNAMIC ANALYSIS AQWA MOORING line tension Motion response HYDRODYNAMIC ANALYSIS
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铁路货车轴承外圈外观检查及手工修磨辅助装置 预览
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作者 张虎 《科技创新与应用》 2019年第35期102-103,共2页
轴承作为铁路车辆的重要组成部分,其结构质量与运行状况对车辆的安全有绝对性的影响,一直被交通管理人员和铁路工程技术人员所关注。在铁路货车的众多组成结构中,货车轴承发挥着不可替代的重要作用,其制造质量的好坏和运行稳定性的高低... 轴承作为铁路车辆的重要组成部分,其结构质量与运行状况对车辆的安全有绝对性的影响,一直被交通管理人员和铁路工程技术人员所关注。在铁路货车的众多组成结构中,货车轴承发挥着不可替代的重要作用,其制造质量的好坏和运行稳定性的高低对铁路货车的安全性有直接的影响,因此为了实现铁路货车稳定安全的运行,就必须保证轴承的质量和工艺。在此背景下,文章就铁路货车轴承一般检修中外圈外观检查以及手工修磨辅助装置进行了探索和研究,希望能够给相关技术人员一定的借鉴,从而共同促进我国铁路运输事业的健康稳定发展。 展开更多
关键词 铁路货车 轴承 外圈 外观检查 手工修磨 装置
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Recent developments in novel silica-based optical fibers
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作者 Ting-yun WANG Fu-fei PANG +3 位作者 Su-juan HUANG Jian-xiang WEN Huan-huan LIU Li-bo YUAN 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第4期481-489,共9页
We have summarized our recent work in the area of novel silica-based optical fibers, which can be classified into two types: silica optical fiber doped with special elements including Bi, Al, and Ce, and micro-structu... We have summarized our recent work in the area of novel silica-based optical fibers, which can be classified into two types: silica optical fiber doped with special elements including Bi, Al, and Ce, and micro-structured multi-core fibers. For element-doped optical fiber, the Bi/Al co-doped silica fibers could exhibit a fluorescence spectrum covering the wavelength range between 1000 and 1400 nm with a full width at half maximum(FWHM) of about 150 nm, which enables its use in fiber amplifiers and laser systems. The Ce-doped fiber’s center wavelengths of excitation and emission are about 340 and 430 nm, respectively. The sapphire-derived fiber(SDF) with high alumina dopant concentration in the core can form mullite through heating and cooling with arc-discharge treatment. This SDF can be further developed for an intrinsic Fabry-Perot interferometric that can withstand 1200 ℃, which allows it to be used in high-temperature sensing applications. Owing to the strong evanescent field, microstructured multi-core fiber can be used in a wide range of applications in biological fiber optic sensing, chemical measurement, and interference-related devices. Coaxial-core optical fiber is another novel kind of silica-based optical fiber that has two coaxial waveguide cores and can be used for optical trapping and micro-particle manipulation by generating a highly focused conical optical field. The recent developments of these novel fibers are discussed. 展开更多
关键词 Optical FIBER FIBER OPTIC DEVICE Silica-based SPECIAL FIBER
鱼道过鱼监测系统的研究与应用 预览
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作者 王世玉 宋海峰 +1 位作者 陈正平 罗招贵 《水电与抽水蓄能》 2019年第3期88-91,87共5页
本文从系统结构、装置结构、软件功能等方面进行研究设计,同时结合国内已建项目应用情况,增加自清洗功能,以提高使用效果、减少维护工作量.研制开发的系统已在新疆某水利枢纽鱼道工程成功应用,可为其他鱼道工程过鱼监测系统的设计、建... 本文从系统结构、装置结构、软件功能等方面进行研究设计,同时结合国内已建项目应用情况,增加自清洗功能,以提高使用效果、减少维护工作量.研制开发的系统已在新疆某水利枢纽鱼道工程成功应用,可为其他鱼道工程过鱼监测系统的设计、建设实施提供借鉴. 展开更多
关键词 鱼道 过鱼监测 自清洗 装置
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A methodology to develop a vascular geometry for in vitro cell culture using additive manufacturing 预览
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作者 Laurene Lenoir Frederic Segonds +1 位作者 Kim-Anh Nguyen Pablo Bartolucci 《国际生物打印期刊》 2019年第2期99-108,共10页
Today,additive manufacturing(AM)is implemented in medical industry and profoundly revolutionizes this area.This approach consists of producing parts by additions of layers of successive materials and offers advantages... Today,additive manufacturing(AM)is implemented in medical industry and profoundly revolutionizes this area.This approach consists of producing parts by additions of layers of successive materials and offers advantages in terms of rapidity,complexity of parts,competitive costs that can be exploited and can lead to a significant advancement in biological research.Everything becomes technically feasible and gives way to a“techno-centered”approach.Many parameters must be controlled in this field,so it is necessary to be guided for the development of such a product.This article aims to present a state of the art of existing design methodologies focused on AM to create medical devices.Finally,a development method is proposed that consists of producing vascular geometry using AM,based on patient data,designed for cell culture in vitro studies. 展开更多
关键词 Innovation Design ADDITIVE MANUFACTURING BIOLOGY Medical device
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Design of a unified rendering shader for mobile device
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作者 Jiang Lin Tian Rujia +1 位作者 Yang Bowen Tian Pu 《中国邮电高校学报:英文版》 EI CSCD 2019年第3期81-90,共10页
Real-time graphics processing is all along a crucial task of mobile device, and it is conventionally supported by programmable graphics processing unit(GPU). These GPUs are designed to flexibly support vertex and pixe... Real-time graphics processing is all along a crucial task of mobile device, and it is conventionally supported by programmable graphics processing unit(GPU). These GPUs are designed to flexibly support vertex and pixel processing with classic techniques such as on-chip cache and dynamic programmable pipelining. However, it is difficult for the vertex shader and pixel shader to achieve high utilization of hardware resources, even though there is a certain balance by reasonable processor quantity ratio. In this paper, a unified render shader with a very long instruction word(VLIW) processor was designed. The viewport transformation algorithm and the Mipmap mapping algorithm are respectively mapped on the shader, with the purpose of providing an energy-efficient and flexible hardware platform for graphics processing in mobile device. The implemented operating frequency is up to 134 MHz on Xilinx XC7 Z045-2-FFG900 field programmable gate array(FPGA), and unified architecture shader has a performance of 134 Mpixels/s in pixel fill rate, 546 Mtexels/s in texel fill rate. 展开更多
关键词 VERTEX SHADING PIXEL SHADER VLIW mobile device GPU
摇摆式波浪能发电装置模型研究 预览
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作者 钟小龙 叶荣春 熊正烨 《中国水能及电气化》 2019年第8期41-43,共3页
波浪能是指波浪表面所具有的动能和势能。尽管波浪能是一种不稳定的能源,但海洋中波浪能巨大而丰富。文章设计了一种摇摆机械式波浪能转化发电装置,将波浪能转化为电能,并测量计算了该装置的转化效率。实验结果表明:该装置的整体转化效... 波浪能是指波浪表面所具有的动能和势能。尽管波浪能是一种不稳定的能源,但海洋中波浪能巨大而丰富。文章设计了一种摇摆机械式波浪能转化发电装置,将波浪能转化为电能,并测量计算了该装置的转化效率。实验结果表明:该装置的整体转化效率可达到45%以上,具有一定的应用潜力;发电机系统的功电转化效率与系统的负载关系很大,选择合适的负载,可使系统功电转化效率保持在较高水平。 展开更多
关键词 波浪能 发电 装置
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DEH控制系统设备脆弱性分析及建议 预览
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作者 张建 《现代制造技术与装备》 2019年第4期208-209,共2页
针对某电厂一、二期DEH系统设备现状及改造情况进行了详细分析,对DEH控制系统设备脆弱性进行了讨论,并提出了具体的改进建议,旨在提升机组运行安全性与稳定性。
关键词 DEH控制系统 设备 脆弱性分析
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